Incinerator

ABSTRACT

An incinerator including a primary combustion chamber and an afterburner or secondary combustion chamber in the base of the stack and at least one connecting passageway between the chambers. The primary combustion chamber has no burner or primary source of ignition; has means to maintain a preset negative air pressure for starved oxygen combustion of rubbish; and operates with a minimum turbulence. The afterburner is tangentially fired by gas and supplied with air to cause high temperature combustion of the smokey off-gas and ash from the primary combustion chamber. Hot flue gases pass into a stack where they are cooled by atmospheric air. The resultant emissions comprise water vapor and a minimal amount of carbon dioxide. A limited amount of ash settles at the base of the primary combustion chamber.

United States Patent n91 DiSabatino May 6, 1975 1 INCINERATOR V Inventor: Sabatino DiSabatino, 29 Waldo Ave., Bloomfield, NJ. 07003 [22] Filed: June 19, 1974 [21] Appl. No.: 480,904

[52] US. Cl 0/8 C; 110/8 A; 110/75 R; 1 10/1 19 [51] Int. Cl. F23g 5/12 [58] Field of Search 110/8 R, 8 A, 8 C, 18 R,

110/18 C, 72 R, 75 R, 119

[56] References Cited UNITED STATES PATENTS 3,552,332 1/1971 Mattenly 110/8 3,651,771 3/1972 Eberle 110/8 3,664,277 5/1972 Chatterjee l 110/8 3,749,031 7/1973 Burden, Jr. 110/8 3,782,301 l/l974 Livengood et al...... 110/8 Primary Examiner-Kenneth W. Sprague Attorney, Agent, or FirmJames J. Cannon, .lr.; James J. Cannon [57] ABSTRACT An incinerator including a primary combustion chamher and an afterbumer or secondary combustion chamber in the base of the stack and at least one connecting passageway between the chambers. The primary combustion chamber has no burner or primary source of ignition; has means to maintain a preset negative air pressure for starved oxygen combustion of rubbish; and operates with a minimum turbulence. The afterburner is tangentially fired by gas and supplied with air to cause high temperature combustion of the smokey off-gas and ash from the primary combustion chamber. Hot flue gases pass into a stack where they are cooled by atmospheric air. The resultant emissions comprise water vapor and a minimal amount of carbon dioxide. A limited amount of ash settles at the base of the primary combustion chamher.

8 Claims, 4 Drawing Figures P/JENTED HAY 5 i975 SHEET 3 BF 3 FIG.4

INCINERATOR BACKGROUND OF THE INVENTION 1. Field of the lnvention This invention pertains to an improved and simplified incinerator for the burning of rubbish and garbage which incinerates waste almost completely, reducing it to water vapor, an acceptable level of carbon dioxide, and a minimal amount of ash. The incinerator of the present invention burns waste in two stages utilizing a primary combustion chamber and an afterburner or secondary combustion chamber. Forty percent of the burning process is accomplished in the primary com bustion chamber in which a preset negative air pressure is maintained. This causes a smokey, smoldering, nonturbulent fire with ash and gases rising into the secondary combustion chamber in which the resultant gases and fire ash are reburned by an afterburner at a considerably higher temperature. The resultant emissions are significantly below federal and state polution standards.

2. Description of the Prior Art The prior art discloses numerous incinerator devices and afterburners for incinerators. The Hoskinson US. Pat. Nos. 3,215,101, 3,248,178 and 3,355,254, all disclose incinerators with afterburners for the reburning of smoke comprising gases and ashes. The afterburner disclosed in these patents is of very complex construction. U.S. Pat. No. 3,610,179 discloses a somewhat simpler incinerator with afterburner, but requires compression of gases before reburning. US. Pat. No. 3,631,823 discloses a tiltable platform for inducing air currents in the primary combustion chamber. US. Pat. No. 3,651,771 discloses an incinerator with afterburner which operates on a substantially different principle from the incinerator of the present invention as disclosed hereinafter. U.S. Pat. No. 3,567,399 discloses an afterburner far more complex than the afterburner of the present invention.

The present invention is similar to the prior art in basics such as having a firebox as a primary combustion chamber, having a transitional passage to a secondary combustion chamber or afterburner for the cumbustion of gases and ashes. However, the incinerator of the present invention differs significantly from the prior art in its principles of operation. The incinerator of the present invention does not have an ignition mechanism in its primary combustion chamber, in contrast to the prior art. Furthermore. the incinerator of the present invention works on a starved oxygen principle. A control system is utilized to maintain a preset negative air pressure within the primary combustion chamber, said pressure being measured at the base of the afterburner stack. Air, and consequently oxygen, can be withdrawn from this chamber until the preset negative air pressure is reached. 1f the pressure should fall below the desired level, the control system reverses the airflow and feeds air into the primary combustion chamber through perforated fire brick at its base until the desired preset negative air pressure is reached. This results in a smoldering, smokey and non-turbulent fire in the primary combustion chamber with hot gases and ash rising slowly into the afterburner or the secondary combustion chamber. The afterburner of the incinerator of the present invention is also different from the prior art in its simplicity. The air control system which maintains a preset negative air pressure in the primary combustion chamber as measured at the base of the afterburner stack also serves to supply some air into the secondary combustion chamber or afterburner along with the normal upward flow of gases and ash. An ignition system at the base of the afterburner jets a flame into the afterburner while air is fed into the afterburner to insure high temperature combustion of the smokey gas and ash. Since the emissions from the primary chamber rise slowly into a very hot afterburner, all the residue and emissions from the primary chamber are changed to water vapor or carbon dioxide to pass through the stack, or ash to fall to a tray at the base of the primary chamber.

The use of a starved oxygen system causes only a very limited smokey fire in the primary combustion chamber with a minimum of turbulence and carry out of ash with the smoke. This, in turn, minimizes the amount of reburning to be done in the afterburner and makes possible a simplified afterburner design.

Hence, the incinerator of the present invention is distinguished from the prior art on the following points:

1. Use of stained oxygen principle:

2. Simplified afterburner;

3. Lack of ignition source in primary combustion chamber;

4. Negative air pressure control system for primary chamber;

5. Minimal turbulence in primary combustion chamber;

6. Simplified loading of charging system.

ln many incinerators disclosed in the prior art, there appear various mechanical loading or charging systems which are expensive to manufacture and are prone to malfunction in use. The incinerator of the present invention is basically designed for small loads, up to 20 tons per day, of rubbish and garbage. Hence, it is designed for the small business and not as a municipal incinerator. In this context, it does not require a mechanical loading system. lts simplified charging system can be fully loaded manually in 20 seconds and reloaded every 2 minutes if necessary. Thus the loading and charging system is far simpler, faster and less expensive than those disclosed in the prior art. All these factors combine to provide a simple, efficient and inexpensive incinerator.

SUMMARY OF THE INVENTION This invention pertains to an improved and simplified, medium-sized incinerator capable of burning up to 20 tons per day of rubbish, garbage and other waste materials, reducing the waste materials to a minimal quantity of sterile ash, water vapor and a minimal acceptable level of carbon dioxide. This incinerator comprises a loading or charging chamber, a primary combustion chamber having no source of ignition, an air pressure and control system which maintains a preset negative air pressure in the primary combustion chamber, measured at the base of the afterburner, an afterburner or secondary combustion chamber above the primary combustion chamber into which smoke and ash rise, an ignition source, such as natural gas. to fire the afterburner for secondary burning of gases and ashes. a stack rising from the afterburner, a source of air to be blown into the stack at multiple locations providing oxygen for complete combustion in the afterburner and a cooling effect on the water vapor and carbon dioxide rising out of the stack, and a spark arrester on top of the stack for safety reasons.

In operation, refuse is loaded manually into a loading chamber by raising a cover door and a paddle pusher and inserting the rubbish into the charging chamber. The cover door and paddle pusher are then closed. A fire door between the charging chamber and the primary combustion chamber is then raised hydraulically into an elevated position provided the charger cover door is closed. As this occurs. the paddle pusher comes down to force the refuse material into the primary combustion chamber. The fire door is then lowered as soon as this new charge of refuse has been pushed into the primary combustion chamber.

If there is no fire in the primary combustion chamber, an ignited torch is inserted through a side door to start combustion.

The incinerator of the present invention operates on a starved oxygen combustion in the primary combustion chamber. Air pressure in this chamber is continuously monitored at the base of the afterburner stack through a pressure guage in the form of a photo-helix switch, connected to an automatic control system. As the limited supply of oxygen in the primary combustion chamber is consumed, additional air for combustion is driven by a fan through a distribution box with an automatic damper which regulates the flow of primary combustion air. This air is delivered into the primary combustion chamber through perforated fire bricks which serve as a fixed grating in the base of the primary combustion chamber.

The automatic controls regulate the flow of air into the primary combustion chamber to maintain a preset negative air pressure in the primary combustion chamber, said pressure being measured at the base of the afterburner stack, thus causing a smoldering, smokey fire in the chamber with a minimum of turbulence and carry-out of ash with the smoke. The smoke and ash rise into an afterburner where a preset flow of fuel gas (natural gas or propane) is jetted into the base of the afterburner to insure complete mixing and combustion. Sec ondary combustion air is supplied through a series of mixing jets in the stack above the afterburner to cause a high temperature combustion of the smokey off-gas. These hot flue gases then pass into the stack where a natural influx of dilution air tends to cool them.

The fan also creates a suction in the loading or charging hopper to remove any smoke which might escape from the primary combustion chamber when its door is raised in the open position. This smoke is ducted to the suction side of the fan and from there into the afterburner.

In summary, the air control system distributes a limited amount of air to the primary combustion chamber to replace oxygen consumed in the burning process. This air, which in continuous use amounts to about thirty percent of the total air used in the incinerator, is distributed from the fan through ducts to the perforated fire brick at the base of the primary combustion chamber and is automatically throttled to maintain the desired preset negative air pressure. Secondary air is distributed by the same fan into the afterburner and stack through a series of tangential nozzles with four nozzles 90 apart in each of five banks.

Fly ash is controlled by the perforated brick which serve as a fixed grate and the limited amount of primary combustion air. which is regulated to achieve a smoldering type of fire with a minimum of break-up of the ash matrix and resulting fly ash. The automatic controls regulate the amount of primary air while maintaining a fixed draft in the primary combustion chamber. The air pressure setting can be adjusted to accomodate the type of refuse that is being incinerated. The controlled combustion in the primary combustion chamber produces a heavy smoke rich in unburned hydrocarbons and carbon monoxide.

For control of the hydrocarbons, smoke and carbon monoxide, the incinerator of the present invention utilizes a high temperature, turbulent afterburner at the base of its stack. Additional fuel is mixed into the offgas rising into the afterburner stack through four tangential nozzles and secondary air is also jetted into the afterburner so that flame is evident throughout the entire afterburner section of the stack. The quantity of fuel gas can be adjusted for the type of refuse being incinerated. The afterburner temperature for typical refuse is about 2,400F.

The combination of a starved oxygen system in the primary chamber producing a smoldering, smokey, non-turbulent combustion and causing hot gases and ash to rise slowly into the afterburner, and a very hot, tangentially fired afterburner for reburning the rising ash and gases, results in virtually complete combustion of the garbage and rubbish, yielding water vapor and a minimal amount of carbon dioxide to be emitted from the smoke stack, and a minimal amount of ash deposited through the brick grating to an ash pan. The incinerator disclosed herein can meet all present and anticipated environmental standards for emission of pollutants.

It is the principle object of the present invention to provide a new and improved incinerator which effects a more efficient burning of waste products and consequently emits virtually no pollutants into the atmospheric environment.

It is a further object of the present invention to provide an improved incinerator which is simple in structure, operation and maintenance, and consequently very inexpensive to manufacture and operate.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a front perspective view of the incinerator of the present invention.

FIG. 2 is a side view of the incinerator of FIG. 1.

FIG. 3 is a cut away view of the incinerator of this invention taken along the lines 3-3 of FIG. 2.

FIG. 4 is a functional schematic diagram of the incinerator of FIG. 2.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring now to the drawings, and in particular to FIGS. 1 to 3 inclusive, wherein like reference numerals denote corresponding parts, incinerator 10 includes a support housing [2 which serves as a cradle-like base on which other major conponents of incinerator 10 are mounted. Incinerator 10 has a primary combustion chamber 14 and an afterburner or secondary combustion chamber 16. A stack 20. comprising five segments. lower stack member or afterburner l6, aspirator ring 21, frustroconical segment 22, upper stack member 23 and spark arrestor 24, is mounted on top of primary combustion chamber 14. Afterburner I6 is mounted at the base of stack 20 in communication at its lower end with said primary combustion chamber 14 and at its upper end with an aspirator ring 21, which in turn is in communication with frustroconical segment 22 and through it with upper stack segment 23 of said stack 20. No burners or other source of ignition are included in the primary combustion chamber 14. A series of tangentially oriented burners 18 is provided at the base of the afterburner or secondary combustion chamber 16 as illustrated in FIG. 4. A spark arrester 24 is mounted on top of the upper stack member 23. An air control system 25, an electrical control system 26, and a charging and loading system 27 complete the basic components of incinerator 10. Each of the components of incinerator will be described hereinafter in detail.

The efficieriey of incinerator 10 results primarily from the operation of the primary combustion chamber 14 and the air control system 25. The primary combustion chamber 14 in the preferred embodiment is contained within a horizontally oriented cylindrical casing 28 mounted on support housing 12, generally elongated along its major axis and generally circular in cross-section along its minor axis. While this configuration of cylindrical casing 28 is preferred from the viewpoint of efficient operation, it is to be understood that casin g 28 may be of any other shape which would function satisfactorily. Each end of cylindrical casing 28 is covered by a vertically oriented circular cover 30, which, on at least one end, is hinged by hinges 32 to enable cover 30 to be opened for inspection, maintenance and the insertion of large articles into the primary combustion chamber [4. Screw bolts 34 are provided to secure cover 30 in a closed position. Cover 30 also has a small hinged door 36 in its center which is opened for manual ignition of refuse material in the primary combustion chamber 14 and for visual inspection of the chamber 14. Both end covers 30 must be in an airtight relationship with casing 28. Casing 28 and covers 30 may be fabricated of any suitable material which will withstand the high temperatures generated within the primary combustion chamber 14 as hereinafter described.

With reference to FIG. 4, primary combustion chamber 14 is formed by lining cylindrical casing 28 with fire and heat resistant materials. Steel grates 38 are angularly positioned along the base of primary combustion chamber 14 and a layer of perforated fire brick 40 is laid circumferentially over said grates 38 thus covering the interior of cylindrical casing 28 to form an arcuate pattern on approximately one-third of the interior wall of said cylindrical casing 28. The remaining surface area of the interior wall of said cylindrical casing 28 is lined with refractory materials 42 over insulation 43. Insulation 43 serves to retain heat in primary combustion chamber 14 and keep cylindrical casing 28 cool. Perforated fire brick 40 over grates 38 serve as a fixed grate in the primary combustion chamber and allow ash residue to fall through to a collection tray 46 in base housing 12. A plurality number of apertures 44 in cylindrical casing 28 enable the residue to fall through to said collection tray 46. Tray 46 may be slideably removed from base 12 for emtying and cleaning. Air ducts 47 at the base ofcylindrical casing are connected to the air control system 24 as hereinafter described. The perforations in perforated fire brick 40 and grate 38 also serve as conduits for the flow of air into and out of the primary combustion chamber 14 under the control of air control system 24 hereinafter described Referring again to FIG. 1, base housing 12 also includes a base platform 48 which extends horizontally outward to support a stepped loading platform 50. Extending laterally outward from cylindrical casing 28 and over loading platform 50 is the charger housing 52 for charger hopper 54, the principal element of changing and loading system 27. Charger housing 52 includes two arcuate shaped sides 56, a base member 58 all fitted to an arcuate portion of cylindrical casing 28. Charger hopper 54 has a hinged cover 60 which can be raised to permit the insertion of rubbish into hopper 54. Cover 60 when lowered and secured makes an airtight fit over sides 56 and base 58 of housing 52. A paddle pusher 62 is also hinged within cover 60 for pushing refuse into the primary combustion chamber 14. That portion 64 of cylindrical casing 28 framed within char ger housing 52 is cut angularly and connected to a hydraulic lifter (not shown) so that it serves as an opening door to the primary combustion chamber 14 from charger hopper 54. After a charge of rubbish is loaded into charger hopper 54, hopper cover 60 is closed with paddle pusher 62 in a raised position adjacent to cover 60. The operator then pushes a button on the electrical control system 26 (hereinafter described) to activate the hydraulic mechanism to raise combustion chamber charging door 64 and then activate a downward swing of paddle pusher 62 through hopper 54 to push a charge of rubbish into the primary combustion chamber 14. Paddle pusher 62 returns to its normal upward position, charging door 64 closes and the incinerator 10 is ready for another charge of refuse. During the time charging door 64 is open some smoke may escape into charging hopper 54 if combustion is taking place. This smoke is exhausted from the hopper by air control system 25 through duct 66.

In the preferred embodiment of incinerator 10, the primary combustion chamber 14 is 68 inches long and 58 inches in diameter. The fixed area of grates 38 and perforated fire brick 40 is 68 inches long and 53 inches along the bottom perimeter wall of cylindrical casing 28. A maximum of 2,375 cubic feet of air can enter primary combustion chamber 14.

Mounted on the top center of cylindrical casing 28 is afterbumer and stack assemble 20. Stack 20 comprises five principal pipe sections as described above; one of which is the afterburner or secondary combustion chamber 16 and the others include the exhaust portion 23 and aspirator ring 21. Afterburner 16 comprises a cylindrical pipe casing 74 fabricated from fire and heat resistant materials and lined with refractory materials on its interior such that, in the preferred embodiment, it is 54 inches high, has an interior diameter at its base of 10 inches and at its peak has an interior diameter of l4 inches. Afterburner 16 is tightly secured to cylindrical casing 28 and positioned over an aperture in casing 28 such that gases and ash in said primary combustion chamber 14 will rise into afterburner 16. Around the base of the perimeter of afterburner 16 there are located four tangential gas jets 76 which supply fuel to the afterbumer 16 as illustrated in FIG. 4. Ignition for this gas is supplied by the electrical control system 26 hereinafter described. Additional oxygen for combustion in the afterbumer 16 is supplied through twenty tangential air jets 78 which are arranged circumferentially about and above the perimeter of said aftcrburner or first stack segment 16 in five groups of four jets each apart and each group 6 inches above the next group. Additional oxygen is supplied through apertures 75 in aspirator ring 21. Air is furnished to said jets 78 from the air control system 25 hereinafter described. As smoke, hydrocarbons and carbon monoxide rise into afterbumer 16, they combine with ignited fuel and air to achieve a high temperatue and turbulent combustion. Flame is visible through the entire afterburner stack section 16. For the average charge of refuse, the temperature in afterbumer 16 is approximately 2,400F. The resultant gases rise through aspirator ring 21 at the base of stack segment 22 permitting the influx of atmospheric air from air control system 25 to cool the rising gases. Stack segment 23 is mounted over stack segment 22 and, in the preferred embodiment, is l6 inches in diameter and extends to 21 feet above the base or ground level. Atmospheric air enters the upper exhaust segment 23 of stack through air jets 75 for cooling purposes. The temperature of stack gases in upper section 23 ranges from 960F to 530F in the preferred embodiment. Upper stack section 23 is also covered by a spark arrester 24. All segments of stack 20 are lined with refractory materials.

The electrical control system 26 of incinerator 10 is housed in a rectangular housing 84 mounted on the rear top of cylindrical casing 28 adjacent to the charging hopper 52 and accessible from platform 50, as shown in FlG. 2. Operator control buttons for activating the hopper door 60, the ignition for afterburner gas jets 76 and activating air control system are located on an exterior panel 86 of housing 84. Also located on panel 86 are air pressure and temperature guages for monitoring air pressure in the primary combustion chamber 14 and the temperature in primary combustion chamber 14, afterburner l6 and stack 20. Electrical control system 26 includes a high voltage transformer to provide a spark for igniting gas from gas jets 76; a low voltage transformer for activating a thermocoupler; relays to activate the hydraulic system that raises and lowers the primary combustion chamber charging door 64, and a photo-helix switch which gives the air pressure in the primary combustion chamber 14. Said photo-helix switch (not shown) is connected by a small air hose 88 to an opening in the top of cylindrical casing 28. Said photo-helix switch is preferably model number 1 12212538 manufactured by Dwyer Instrument Company. Gas valves for the control of gas jets 76 are also on panel 86. Electrical control system 26 also supplies all the electrical power necessary for the air control system 25 described below.

Air control system 25 includes a pressure opening 90 located at the base of afterburner 16 which diverts some air pressure in the primary combustion chamber 14 at this point and communicates this to a guage 88 on the control panel 86 and to the photo-helix switch. A fan 92 mounted in base housing 12 drives air through a distribution box 94 with an automatic damper 96 into hoses 98, 100. Hose 98 delivers air to the afterburner l6 and aspirator ring 21 of stack 20.

The flow of air to primary combustion chamber 14 is regulated by the photohelix switch. The exact negative air pressure is determined by the type of refuse being burned. A desirable negative air pressure is preset in a pressure regulator (not shown) in control box 84. If the air pressure in the primary chamber 14 becomes too negative for the desired combustion, the photo-helix switch trips a margal valve (not shown) to activate the automatic damper 96 to open and permit a greater volume of air to move through base 100 to the primary combustion chamber 14. The balance of the air driven by fan 92 through distribution box 94 passes to the afterbumer l6 and aspirator ring 21 of stack 20. Fan 92 also draws a suction on charging hopper 54 to remove any smoke which could enter hopper 54 when primary combustion chamber hopper door 64 is raised to allow a new charge of rubbish to be loaded. This smoke is exhausted through hose 66 and ducted to the suction side of fan 92. As is evident from the foregoing description of air control system 25, there is no overfire air supplied to primary combustion chamber 14.

While there have been described herein what are at present considered preferred embodiments of the invention, it will be obvious to those skilled in the art that modifications and changes may be made therein without departing from the principles and scope of this invention. It is therefore to be understood that the exemplary embodiments are illustrative and not restrictive of the invention, the scope of which is defined in the appended claims, and that all modifications that come within the meaning and range of equivalency of the claims are intended to be included therein.

I claim:

1. An improved incinerator for complete combustion of waste materials comprising:

a base housing;

an elongated casing member mounted on said housing and defining a primary combustion chamber; steel grates mounted along the base of said primary combustion chamber;

perforated fire brick mounted on said steel grates,

said grates and brick forming a fixed grate on which said waste materials are burned and through which resultant ash can fall;

means to collect and remove said ash;

means to load waste materials into said primary combustion chamber;

a stack assembly unit mounted on said primary combustion chamber;

an afterburner unit mounted at the base of said stack assembly unit;

an aspirator ring mounted in said stack assembly unit above said afterburner;

a spark arrester mounted on top of said stack assema fan and ducts connected thereto to supply air to the primary combustion chamber and the afterburner;

an air control system to maintain a negative air pressure in said primary combustion chamber to insure a slow smoldering smokey non-turbulent fire therein;

means to supply power and fuel to said incinerator.

2. The improved incinerator as defined in claim I wherein said means to collect and remove ash comprise:

perforations in said elongated casing beneath said grate;

a removable tray at the base of said housing and below said perforations.

3. The improved incinerator as defined in claim 1 wherein said means to load waste materials into said primary combustion chamber comprises:

a charging hopper mounted on said cylindrical casing having sides, top and bottom;

a door on said charger housing opening to permit the insertion of a charge of waste materials;

a door within said hopper communicating with said primary combustion chamber to permit the insertion of rubbish from said hopper to said combustion chamber;

means within said hopper to move said rubbish from said hopper through said second door into said primary combustion chamber.

4. The incinerator as defined in claim 1 wherein the interior of said casing forming said primary combustion chamber is lined with insulation and refractory materials on all surfaces other than those covered by said steel grates and perforated fire brick.

5. The incinerator as defined in claim 1 wherein said stack assembly further comprises:

a first stack segment mounted on and in communication with said primary combustion chamber;

an aspirator ring mounted over said first stack segment;

a second stack segment mounted over said aspirator ring;

a spark arrester mounted on top of said second stack segment.

6. The incinerator as defined in claim 5 wherein said afterburner comprises:

four fuel jets placed ninety degrees apart at the base of said first stack segment and aimed tangentially to the radius of said first stack segment;

a plurality of apertures placed ninety degrees apart and in banks above said fuel jets for the introduction of oxygen into said afterburner.

7. The incinerator as defined in claim 6 wherein said aspirator ring further comprises:

means to join said second stack segment to said first stack segment;

apertures in said aspirator ring to permit the introduction of atmospheric air.

8. The incinerator as defined in claim 1 wherein said air control system comprises:

a fan mounted in said housing;

means for said fan to draw atmospheric air;

a distribution box connected to said fan and provided with an automatic damper;

a plurality of air hoses leading from said distribution box to apertures in the base of said primary combustion chamber and in communication therewith whereby air can be distributed to said primary combustion chamber through said grates and perforated fire brick;

a plurality of air inlets in said first stack segment for the introduction of air into said afterburner;

an air hose connecting said afterburner inlets to said distribution box;

an air hose connected between and in communication with said charging hopper and said distribution box to exhaust smoke from said charging hopper;

an air pressure measuring and regulating device in communication with the base of said afterburner;

means to preset said air pressure and regulating device to a negative air pressure in said primary combustion chamber;

means to connect said air pressure measuring and regulating device to said damper to control the flow of air into said primary combustion chamber to maintain a preset negative air pressure in said chamber. 

1. An improved incinerator for complete combustion of waste materials comprising: a base housing; an elongated casing member mounted on said housing and defining a primary combustion chamber; steel grates mounted along the base of said primary combustion chamber; perforated fire brick mounted on said steel grates, said grates and brick forming a fixed grate on which said waste materials are burned and through which resultant ash can fall; means to collect and remove said ash; means to load waste materials into said primary combustion chamber; a stack assembly unit mounted on said primary combustion chamber; an afterburner unit mounted at the base of said stack assembly unit; an aspirator ring mounted in said stack assembly unit above said afterburner; a spark arrester mounted on top of said stack assembly; a fan and ducts connected thereto to supply air to the primary combustion chamber and the afterburner; an air control system to maintain a negative air pressure in said primary combustion chamber to insure a slow smoldering smokey non-turbulent fire therein; meAns to supply power and fuel to said incinerator.
 2. The improved incinerator as defined in claim 1 wherein said means to collect and remove ash comprise: perforations in said elongated casing beneath said grate; a removable tray at the base of said housing and below said perforations.
 3. The improved incinerator as defined in claim 1 wherein said means to load waste materials into said primary combustion chamber comprises: a charging hopper mounted on said cylindrical casing having sides, top and bottom; a door on said charger housing opening to permit the insertion of a charge of waste materials; a door within said hopper communicating with said primary combustion chamber to permit the insertion of rubbish from said hopper to said combustion chamber; means within said hopper to move said rubbish from said hopper through said second door into said primary combustion chamber.
 4. The incinerator as defined in claim 1 wherein the interior of said casing forming said primary combustion chamber is lined with insulation and refractory materials on all surfaces other than those covered by said steel grates and perforated fire brick.
 5. The incinerator as defined in claim 1 wherein said stack assembly further comprises: a first stack segment mounted on and in communication with said primary combustion chamber; an aspirator ring mounted over said first stack segment; a second stack segment mounted over said aspirator ring; a spark arrester mounted on top of said second stack segment.
 6. The incinerator as defined in claim 5 wherein said afterburner comprises: four fuel jets placed ninety degrees apart at the base of said first stack segment and aimed tangentially to the radius of said first stack segment; a plurality of apertures placed ninety degrees apart and in banks above said fuel jets for the introduction of oxygen into said afterburner.
 7. The incinerator as defined in claim 6 wherein said aspirator ring further comprises: means to join said second stack segment to said first stack segment; apertures in said aspirator ring to permit the introduction of atmospheric air.
 8. The incinerator as defined in claim 1 wherein said air control system comprises: a fan mounted in said housing; means for said fan to draw atmospheric air; a distribution box connected to said fan and provided with an automatic damper; a plurality of air hoses leading from said distribution box to apertures in the base of said primary combustion chamber and in communication therewith whereby air can be distributed to said primary combustion chamber through said grates and perforated fire brick; a plurality of air inlets in said first stack segment for the introduction of air into said afterburner; an air hose connecting said afterburner inlets to said distribution box; an air hose connected between and in communication with said charging hopper and said distribution box to exhaust smoke from said charging hopper; an air pressure measuring and regulating device in communication with the base of said afterburner; means to preset said air pressure and regulating device to a negative air pressure in said primary combustion chamber; means to connect said air pressure measuring and regulating device to said damper to control the flow of air into said primary combustion chamber to maintain a preset negative air pressure in said chamber. 